A gas turbine engine generally includes a compressor section, a combustor section, a turbine section and an exhaust section. In operation, the compressor section may induct ambient air and compress it. The compressed air from the compressor section enters one or more combustors in the combustor section. The compressed air is mixed with the fuel in the combustors, and the air-fuel mixture can be burned in the combustors to form a hot working gas. The hot working gas is routed to the turbine section where it is expanded through alternating rows of stationary airfoils and rotating airfoils and used to generate power that can drive a rotor. The expanded gas exiting the turbine section may then be exhausted from the engine via the exhaust section.
In a typical gas turbine engine, bleed air comprising a portion of the compressed air obtained from one or more stages of the compressor may be used as cooling air for cooling components of the turbine section. Additional bleed air may also be supplied to portions of the exhaust section, such as to cool portions of the exhaust section and maintain a turbine exhaust case below a predetermined temperature through a forced convection air flow provided within an outer casing of the engine. Advancements in gas turbine engine technology have resulted in increasing temperatures, and associated outer case deformation due to thermal expansion. Case deformation may increase stresses in the case and in components supported on the case within the engine, such as bearing support struts. The additional stress, which may operate in combination with low cycle fatigue, may contribute to cracks, fractures or failures of the bearing support struts that are mounted to the casing for supporting an exhaust end bearing housing.